Flatten Array

Challenge Overview

Take a nested list and return a single list with all values except nil/null.

Visit the flatten-array exercise on Exercism to read the full instructions and download the exercise files.

Community Solutions

View Community Solutions

The following are the top 3 community solutions by stars:

Solution 1 by @ErikSchierboom (⭐ 3) — View on Exercism
Solution 2 by @pf981 (⭐ 0) — View on Exercism
Solution 3 by @fravan (⭐ 0) — View on Exercism

Source: Exercism gleam/flatten-array

💡 View Solution

pub type NestedList(a) {
  Null
  Value(a)
  List(List(NestedList(a)))
}

pub fn flatten(nested_list: NestedList(a)) -> List(a) {
  case nested_list {
    Null -> []
    Value(a) -> [a]